Epipubic bone

Epipubic bones are a pair of bones projecting forward from the pelvic bones of modern marsupials, monotremes and fossil mammals like multituberculates, and even basal eutherians (the ancestors of placental mammals, who lack them).^[1] They first occur in non-mammalian cynodonts such as tritylodontids, suggesting that they are a synapomorphy between them and Mammaliformes.

They were first described as early as 1698, but to date, their function(s) remain unresolved.^[2] Epipubic bones are often called marsupial bones because they support the mother's pouch in modern marsupials ("marsupium" is Latin for "pouch").^[3]

^ Novacek, M.J.; Rougier, G.W.; Wible, J.R.; McKenna, M.C.; Dashzeveg, D.; Horovitz, I. (1997). "Epipubic bones in eutherian mammals from the late Cretaceous of Mongolia". Nature. 389 (6650): 440–1. Bibcode:1997Natur.389..483N. doi:10.1038/39020. PMID 9333234. S2CID 205026882.
^ Cite error: The named reference Reilly-White-2003-01-17 was invoked but never defined (see the help page).
^ Cite error: The named reference White-1989 was invoked but never defined (see the help page).

[1] Novacek, M.J.; Rougier, G.W.; Wible, J.R.; McKenna, M.C.; Dashzeveg, D.; Horovitz, I. (1997). "Epipubic bones in eutherian mammals from the late Cretaceous of Mongolia". Nature. 389 (6650): 440–1. Bibcode:1997Natur.389..483N. doi:10.1038/39020. PMID 9333234. S2CID 205026882.

[Reilly-White-2003-01-17-2] Cite error: The named reference Reilly-White-2003-01-17 was invoked but never defined (see the help page).

[White-1989-3] Cite error: The named reference White-1989 was invoked but never defined (see the help page).

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